HistoryManager methods overview
| Name | Description |
|---|---|
| add() | Adds a new state |
| disable() | Blocks HistoryManager |
| enable() | Restarts the work of HistoryManager, saving the current state as initial state |
| isRedo() | Checks whether the current HistoryManager state is in the ending state |
| redo() | Takes a step forward in the history of changes |
| reset() | Resets previous changes and saves the current state |
| undo() | Takes a step back in the history of changes |